Management of spongy moth in yards is more intensive than in woodlands.  Caterpillar frass (chewed leaves, feces, irritating shed hairs) can become a problem in yards. 

Wisconsin Spongy Moth portal includes yard management and seasonal control.

If you have spongy moth, let your neighbors know so they can watch for it.  Infestations are often isolated at first, but can spread to adjoining properties. 

DO NOT destroy caterpillars and eggs with torches or any chemical or means that can harm your trees above or below ground. 

Yard tree health can be a concern if the trees are already stressed by disease, drought, or other factors. For general guidance on yard tree health, contact the UW Extension - Rock County  horticulturist.

If you need help managing infestations and tree health on your property, contact a certified arborist. 

 If you have concerns about infestations on public property, contact your municipality or manager of the property.

Management of spongy moth on wood lots is different than in yards. 

Wisconsin Spongy Moth portal includes information on wood lot management quarantine areas. 

Caterpillars hatch in late April and disperse by using a silk strands to balloon off tall objects or get caught on passing vehicles or deer moving through infested areas. Common places to find activity are along driveways, garages, and wood piles.

Caterpillars migrate daily to feed then rest in sheltered areas nearby.  This instinct is used to trap caterpillars May through June.  

Egg masses - where to look (August - April).  By late June, the caterpillars will stop feeding and crawl to sheltered niches to pupate.  These niches can be under flaky bark of any tree, under tree limbs, bottom edges of trim/siding, bird houses, signs, eaves, outdoor furniture, firewood, lumber, vehicles, trailers, etc. 

Early detection, management, and working with neighbors are keys to success.